Exploring the Effects of Sweet Potato Leaves on Skin Health—From Antimicrobial to Immunomodulator

Sweet potato leaves (SPL), an agricultural byproduct, hold significant potential in dermatological applications due to their bioactive compounds. This study evaluates the phenolic profile of SPL extracts and investigates their biological activities relevant to skin health. Extract fingerprinting, through uHPLC-DAD and LC-MS, identified phenolic acids and flavonoids, with cynarin, neochlorogenic acid, and spiraeoside being predominant. The presence of hyperoside was detected. From a biological standpoint, SPL demonstrated notable antimicrobial activity, with MICs ranging from 2.5 to 5 mg/mL against various bacterial strains, such as MRSA and <i>P. aeruginosa</i>, and effective antibiofilm activity, as it reduced biofilm formation by over 80% for most tested strains. When evaluating its effect upon keratinocytes, the cytotoxicity assessment revealed safe usage concentrations at 111 µg/mL and immunomodulatory capacities, as it increased IL-6 production in unchallenged cells but had no synergistic effects under inflammatory stimuli. While preliminary, and with more assays being necessary, these findings highlight SPL's potential as a natural agent for antimicrobial and anti-inflammatory applications in skin-related applications and open a new avenue for a possible added value application of SPL.